MEXICO CITY, Aug 21 (Reuters) - An oil pipeline spill that contaminated a river in the northern Mexican state of Nuevo Leon will take months to clean up, the country's top water authority said on Thursday.
The 24-inch Madero-Cadereyta pipeline, owned by national oil company Pemex, was ruptured when thieves attempted to tap into it, the company said on Sunday.
The pipeline feeds crude to Pemex's nearby Cadereyta refinery.
David Korenfeld, head of Mexico's national water commission, told reporters in Mexico City that the spill extended across a 6 kilometer (4 mile) stretch of the Rio San Juan, but had been contained by floating barriers.
"The clean-up of this stretch will take approximately two to three months," he said.
Korenfeld added that residents near the contaminated parts of the river, located about 40 kilometers (25 miles) from the state capital of Monterrey, were advised not to consume the water.
Pemex said in its statement on Sunday morning that an illegal tap on the pipeline caused the spill but that it had been controlled.
The statement made no mention of contamination to the river.
Reporting by David Alire Garcia and Adriana Barrera; Editing by Dan Grebler